Ground fault circuit interrupting (GFCI) devices have become widely accepted as effective means for protecting humans from the hazards of electrical shock. The 1975 National Electric Code defines a GFCI device as one "whose function is to interrupt the electric circuit to the load when a fault current to ground exceeds some predetermined value that is less than that required to operate the overcurrent protective device of the supply circuit". Originally, GFCI devices were provided in circuit breaker configurations for installation in existing service entry equipment, i.e., circuit breaker load centers. Later, GFCI devices were provided in receptacle configurations for installation in existing wall outlet boxes. Since the installation of these two GFCI configurations involves a certain amount of actual wiring, they are largely dedicated to the circuit in which they are installed.
Recently, some manufacturers have introduced a so-called "portable" GFCI device which can be plugged into a conventional wall receptacle and is adapted to afford ground fault protection to any load circuit plugged into it. In this configuration, the GFCI device can simply be unplugged from one receptacle and plugged into another receptacle at a location more convenient to the load circuit for which ground fault protection is desired.
It is accordingly an object of the present invention to provide an improved portable GFCI device.
A further object is to provide a portable GFCI device of the above-character which is constructed to utilize an existing GFCI receptacle.
Still another object of the present invention is to provide a portable GFCI device of the above-character having improved mounting provisions adapting the device for safe and reliable physical attachment to and electrically connected with a conventional electrical wall receptacle.
An additional object is to provide a portable GFCI device of the above-character which is efficient in design, inexpensive to manufacture and safe to use.
Other objects of the invention will in part be obvious and in part appear hereinafter.